Digitalis Uses, Benefits & Dosage - Drugs.com Herbal Database Adverse reactions are generally related to toxicity. Toxicology All parts of the plant are toxic. The incidence of digitalis toxicity in therapeutic use has been estimated to range from 5% to 25%. Ingestion of extremely small amounts of the plant may be fatal to humans, especially children, and to animals. Toxicity is cumulative. Botany Digitalis is typically a biennial plant but may be annual or perennial depending on the species. It is characterized by a thick, cylindrical, downy stem that reaches a height of up to 2 m. Leaves form a thick rosette during the first year of growth. The leaves, which are woolly, veined, and covered with white hairs on the underside, have a very bitter taste. Flowers grow in the first or second year, depending on the species, and are tubular and bell-shaped, growing to 8 cm in length. Many colors of flowers have been bred from digitalis, and they are rarely white. Digitalis is native to the British Isles, western Europe, and parts of Africa, but is found today as an ornamental plant throughout the world.

Related species that have found some use in traditional medicine include Digitalis lutea (straw foxglove), Digitalis grandiflora and Digitalis ambigua (yellow foxglove), and Digitalis ferriginea (rusty foxglove). 1 , 2 , 3 History Digitalis was one of the many herbal remedies used by the ancient Romans. Although its use for the treatment of heart failure has been traced back to 10th century Europe, digitalis was not widely used for this indication until its scientific investigation by British physician William Withering in the late 1700s. For most of the 1800s, digitalis was used to treat a wide variety of diseases and disorders. In 1875, German chemist Oswald Schmiedeberg first isolated pure digitoxin from digitalis, leading others to extract and identify other glycosides from various species of digitalis. In 1957, digoxin was isolated from D. lanata and is now a major cardiac glycoside marketed in tablet form.

Digitalis was admitted into the first edition of the Pharmacopeia of the United States (1820) and is currently recognized by all major pharmacopeias. In South America, preparations of the powdered leaves are used to relieve asthma, as sedatives, and as diuretic/cardiotonics. In India, an ointment containing digitalis glycosides is used to treat wounds and burns. 2 , 4 , 5 Chemistry Ornamental strains of D. purpurea typically have low concentrations of active compounds. Leaves of wild varieties that have been used for medicinal purposes contain at least 30 different glycosides in total quantities ranging from 0.1% to 0.6%; these consist primarily of purpurea glycoside A (yielding digitoxin) and glycoside B, the precursor of gitoxin. Upon hydrolysis, digitoxin and gitoxin lose sugar moieties, producing their respective aglycones, digitoxigenin and gitoxigenin. Biosynthetic pathways in the production of cardenolides are reliant on the enzymes of malonyltransferase and progesterone 5 beta-reductase. The main glycosides of D.

lanata are the lanatosides, designated A through E. Removal of acetate groups and sugars results in formation of digitoxin, gitoxin, digoxin, digitalin, and gitaloxin. D. lanata is not typically used in powder form in the United States, but serves as a major source of lanatoside C and digoxin (300 times more potent than the powder prepared from D. purpurea ). Isolated digitoxin is 1,000 times more potent than whole powdered leaves and is completely and rapidly absorbed from the GI tract. The seeds also contain digitalis glycosides, while steroidal saponins, flavones, the flavonoid chrysoeriol, anthraquinones, and organic acids have been identified in the leaves. High performance liquid chromatography and mass spectroscopy have been used to identify and quantify glycoside composition.

2 , 3 , 6 , 7 , 8 , 9 , 10 , 11 Uses and Pharmacology Cardiovascular effects Cardiac glycosides possess positive inotropic effects due to inhibition of sodium-potassium adenosine triphosphatase, which allows calcium to accumulate in myocytes leading to enhanced cardiac contractility. These drugs also possess some antiarrhythmic activity, but will induce arrhythmias at higher dose levels. 7 , 12 , 13 Animal data Studies in animals center largely on evaluations of individual chemical compounds on isolated cardiac and other tissues. 12 , 13 , 14 Clinical data Digitalis glycosides have been used clinically for the treatment of heart failure for more than 200 years and remain the source of commercial digoxin preparations; however, a defined place in therapy remains under debate. Reviews of the large, multicenter Digitalis Investigation Group trial and other clinical trials have found no clear effect of digitalis on mortality in heart failure. Some effect has been demonstrated for secondary outcomes of decreased hospitalizations and clinical (symptomatic) deterioration. 5 , 15 For further information, consult standard pharmacology references.

Other effects Cancer In vitro experiments and screening studies have shown cytotoxic properties of glycosides and flavonoids from D. purpurea and D. lantana . Activity against human cancer cell lines, including solid tumor lines, has been demonstrated. Mechanisms include direct cytotoxicity resulting in apoptosis, inhibition of aflatoxin-induced cytotoxicity, inhibition of induction of nitric oxide synthase, and increases in glutathione S-tranferase. 11 , 16 , 17 , 18 , 19 Diabetes A study in hyperglycemic and dyslipidemic rats demonstrated enhanced glucose tolerance 2 hours after the rats were given a single dose of the saponin digitonin. Positive effects on the lipid profile were also observed. 20 Dosage Digitalis leaf has a narrow therapeutic index, requiring close medical supervision for safe use. Traditional dosage starts at 1.5 g of leaf divided into 2 daily doses. Purified digoxin is typically used at daily doses of 0.125 to 0.25 mg. 15 , 21 Pregnancy/Lactation Adverse reactions are generally related to toxicity.

Toxicology All parts of the plant are toxic. Animal toxicity occurs during grazing. Children have become ill by sucking the flowers or ingesting seeds or parts of the leaves. Deaths have been reported among people who drank tea made from digitalis mistakenly identified as comfrey, although the bitter taste often deters ingestion, and its emetic properties can induce vomiting, thereby limiting systemic absorption. Digitalis poisoning is also associated with intentional ingestion with suicidal intent. 24 , 25 , 26 Digitalis glycosides accumulate and are excreted slowly; therefore, intoxications during therapy are common. The incidence of digitalis toxicity has been estimated to range from 5% to 23%. More stringent dosing guidelines and monitoring techniques have dramatically reduced the incidence of therapeutic overdose. Signs of plant or purified drug poisoning include blurred vision, contracted pupils, dizziness, excessive urination, fatigue, muscle weakness, nausea, strong but slowed pulse, tremors, and vomiting; in severe cases, stupor, confusion, convulsions, and death can occur. Cardiac signs include atrial arrhythmias and atrioventricular block. Chronic digitalis intoxication is characterized by visual halos, yellow-green vision, and GI upset.

2 , 13 , 24 , 27 In mild cases of toxicity (atrial fibrillation with a slow ventricular response or occasional ectopic beats), temporary withdrawal of the drug and electrocardiogram monitoring is sufficient. 6 Gastric lavage or emesis together with supportive measures, such as electrolyte replacements, antiarrhythmics (eg, lidocaine, phenytoin), and atropine, have been used to manage acute poisonings. Digoxin-specific Fab antibody fragments may be used in managing acute intoxications caused by digitalis and related cardioactive glycosides; however, their efficacy remains unproven by controlled clinical trials. 13 , 25 , 28 , 29 Bibliography 1. Digitalis purpurea L. USDA, NRCS. 2010. The PLANTS Database ( March 2010 ). National Plant Data Center, Baton Rouge, LA 70874-4490 USA. 2. Morton JF. Major Medicinal Plants . Springfield, IL: Charles C. Thomas; 1977. 3. Warren B. Digitalis purpurea. Am J Cardiol .

2005;95(4):544. 4. Belcastro PF. Digitalis: from folklore remedy to valuable drug. J Am Pharm Assoc (Wash) . 2002;42(6):857. 5. Feussner JR, Feussner DJ. Reassessing the efficacy of digitalis: from routine treatment to evidence-based medicine. Am J Med Sci . 2010;339(5):482-484. 6. Trease GE. Trease and Evans' Pharmacognosy . 13th ed. London, UK: Balliere Tindall; 1989. 7. Kuate SP, Pádua RM, Eisenbeiss WF, Kreis W. Purification and characterization of malonyl-coenzyme A: 21-hydroxypregnane 21-O-malonyltransferase (Dp21MaT) from leaves of Digitalis purpurea L. Phytochemistry . 2008;69(3):619-626. 8. Usai M, Atzei AD, Marchetti M.

Cardenolides content in wild Sardinian Digitalis purpurea L. populations. Nat Prod Res . 2007;21(9):798-804. 9. Gavidia I, Tarrío R, Rodríguez-Trelles F, Pérez-Bermúdez P, Seitz HU. Plant progesterone 5beta-reductase is not homologous to the animal enzyme. Molecular evolutionary characterization of P5betaR from Digitalis purpurea . Phytochemistry . 2007;68(6):853-864. 10. Kite GC, Porter EA, Simmonds MS. Chromatographic behaviour of steroidal saponins studied by high-performance liquid chromatography-mass spectrometry. J Chromatogr A . 2007;1148(2):177-183. 11. Choi DY, Lee JY, Kim MR, Woo ER, Kim YG, Kang KW. Chrysoeriol potently inhibits the induction of nitric oxide synthase by blocking AP-1 activation. J Biomed Sci .

2005;12(6):949-959. 12. Keenan SM, DeLisle RK, Welsh WJ, Paula S, Ball WJ Jr. Elucidation of the Na+, K+-ATPase digitalis binding site. J Mol Graph Model . 2005;23(6):465-475. 13. Hauptman PJ, Kelly RA. Digitalis. Circulation . 1999;99(9):1265-1270. 14. Navarro E, Alonso PJ, Alonso SJ, et al. Cardiovascular activity of a methanolic extract of Digitalis purpurea spp. heywoodii . J Ethnopharmacol . 2000;71(3):437-442. 15. Hood, Jr. WB, Dans AL, Guyatt GH, Jaeschke R, McMurray JJ. Digitalis for treatment of congestive heart failure in patients in sinus rhythm. Cochrane Database Syst Rev . 2004;(2):CD002901.

doi: 10.1002/14651858.CD002901.pub2 . 16. López-Lázaro M, Palma De La Peña N, Pastor N, et al. Anti-tumour activity of Digitalis purpurea L. subsp. heywoodii . Planta Med . 2003;69(8):701-704. 17. Lindholm P, Gullbo J, Claeson P, et al. Selective cytotoxicity evaluation in anticancer drug screening of fractionated plant extracts. J Biomol Screen . 2002;7(4):333-340. 18. Johansson S, Lindholm P, Gullbo J, Larsson R, Bohlin L, Cleason P. Cytotoxicity of digitoxin and related cardiac glycosides in human tumor cells. Anticancer Drugs . 2001;12(5):475-483. 19. Lee JY, Woo E, Kang KW. Screening of new chemopreventive compounds from Digitalis purpurea .

Pharmazie . 2006;61(4):356-358. 20. Ebaid GM, Faine LA, Diniz YS, et al. Effects of digitonin on hyperglycaemia and dyslipidemia induced by high-sucrose intake. Food Chem Toxicol . 2006;44(2):293-299. 21. Dec GW. Digoxin remains useful in the management of chronic heart failure. Med Clin North Am . 2003;87(2):317-337. 22. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook . Boca Raton, FL: CRC Press; 1997. 23. Tatro DS, ed. Drug Interaction Facts . St. Louis, MO: Wolters Kluwer Health Inc; 2004. 24. Jowett N. Foxglove poisoning. Hosp Med . 2002;63(12):758-759. 25.

Lacassie E, Marquet P, Martin-Dupont S, Gaulier JM, Lachâtre G. A non-fatal case of intoxication with foxglove, documented by means of liquid chromatography-electrospray-mass spectrometry. J Forensic Sci . 2000;45(5):1154-1158. 26. Lin CC, Yang CC, Phua DH, Deng JF, Lu LH. An outbreak of foxglove leaf poisoning. J Chin Med Assoc . 2010;73(2):97-100. 27. Dick M, Curwin J, Tepper D. Digitalis intoxication recognition and management. J Clin Pharmacol . 1991;31(5):444-447. 28. Wickersham RM, Novak K, managing eds. Drug Facts and Comparisons . St. Louis, MO: Facts and Comparisons; 2004. 29. Roberts DM, Buckley NA. Antidotes for acute cardenolide (cardiac glycoside) poisoning. Cochrane Database Syst Rev .

2006;(4):CD005490. doi:10.1002/14651858.CD005490.pub2 . Copyright © 2009 Wolters Kluwer Health Digoxin Uses, Dosage & Side Effects - Drugs.com Pricing & Coupons What is digoxin? Digoxin is derived from the leaves of a digitalis plant. Digoxin helps make the heart beat stronger and with a more regular rhythm. Digoxin is used to treat heart failure . Digoxin is also used to treat atrial fibrillation , a heart rhythm disorder of the atria (the upper chambers of the heart that allow blood to flow into the heart). Important information You should not use digoxin if you have ventricular fibrillation (a heart rhythm disorder of the ventricles, or lower chambers of the heart that allow blood to flow out of the heart).

Slideshow Drug Prices Gone Wild: 10 Old Drugs, 10 New Pricetags Before taking this medicine You should not use digoxin if you are allergic to it, or if you have ventricular fibrillation (a heart rhythm disorder of the ventricles, or lower chambers of the heart that allow blood to flow out of the heart). To make sure digoxin is safe for you, tell your doctor if you have: a serious heart condition such as "sick sinus syndrome" or "AV block" (unless you have a pacemaker); a recent history of heart attack; Wolff-Parkinson-White Syndrome (sudden fast heartbeats); kidney disease; an electrolyte imbalance (such as low levels of calcium, potassium, or magnesium in your blood); if you are malnourished or have recently been sick with vomiting or diarrhea; or if you take a diuretic (water pill), or use steroid medicine. It is not known whether digoxin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant. Digoxin can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

How should I take digoxin? Take digoxin exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended. Try to take the medication at the same time every day. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one. While using digoxin, you may need frequent blood tests. Your kidney function may also need to be checked. Use digoxin regularly even if you feel fine or have no symptoms. Get your prescription refilled before you run out of medicine completely. You should not stop using digoxin suddenly. Stopping suddenly may make your condition worse. Store at room temperature away from moisture and heat. See also: Dosage Information (in more detail) What happens if I miss a dose? Take the missed dose as soon as you remember. Skip the missed dose if your next dose is less than 12 hours away. Do not take extra medicine to make up the missed dose. What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of digoxin can be fatal. What should I avoid while taking digoxin? Avoid becoming overheated or dehydrated during exercise, in hot weather, or by not drinking enough fluids. Digoxin overdose can occur more easily if you are dehydrated. Digoxin side effects Get emergency medical help if you have signs of an allergic reaction to digoxin: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have: nausea, vomiting, loss of appetite; fast, slow, or uneven heart rate; bloody or black, tarry stools; blurred vision, yellowed vision; or confusion, hallucinations, unusual thoughts or behavior. Serious side effects may be more likely in older adults and those who are ill or debilitated.

Common digoxin side effects may include: nausea, diarrhea; Usual Adult Dose of Digoxin for Congestive Heart Failure: Rapid Digitalization with a Loading Dose: Peak digoxin body stores of 8 to 12 mcg/kg generally provide a therapeutic effect with minimum risk of toxicity in most patients with heart failure and normal sinus rhythm. The loading dose should be administered in several fractions, with approximately half the total given as the first dose. Additional fractions of the total dose may be given at 6 to 8 hour intervals. Careful assessment of the patient's clinical response should be considered before each additional dose. If the patient's response necessitates a change from the calculated loading dose of digoxin, then calculation of the maintenance dose should be based upon the amount actually given. Tablets: Initial: 500 to 750 mcg usually produces a detectable effect in 0.5 to 2 hours with a maximal effect in 2 to 6 hours. Additional doses of 125 to 375 mcg may be given at 6 to 8 hour intervals until clinical evidence of an adequate effect is noted.

The usual amount of digoxin tablets that a 70 kg patient requires to achieve 8 to 12 mcg/kg peak body stores is 750 to 1250 mcg. Capsules: Initial: 400 to 600 mcg of digoxin capsules generally produces a detectable effect in 0.5 to 2 hours with a maximal effect in 2 to 6 hours. Additional doses of 100 to 300 mcg may be given cautiously at 6 to 8 hour intervals until clinical evidence of an adequate effect is noted. The usual amount of digoxin capsules that a 70 kg patient requires to achieve 8 to 12 mcg/kg peak body stores is 600 to 1000 mcg. Injection: Initial: 400 to 600 mcg of digoxin intravenously usually produces a detectable effect in 5 to 30 minutes with a maximal effect in 1 to 4 hours. Additional doses of 100 to 300 mcg may be given cautiously at 6 to 8 hour intervals until clinical evidence of an adequate effect is noted.

The usual amount of digoxin injection that a 70 kg patient requires to achieve 8 to 12 mcg/kg peak body stores is 600 to 1000 mcg. The injectable route is frequently used to achieve rapid digitalization, with conversion to digoxin tablets or digoxin capsules for maintenance therapy. Maintenance Dose: The doses of digoxin tablets used in controlled trials in patients with heart failure have ranged from 125 to 500 mcg once daily. In these studies, the digoxin dose has been generally titrated according to the patient's age, lean body weight, and renal function. Therapy is generally initiated at a dose of 250 mcg once daily in patients under age 70 with good renal function. Usual Adult Dose for Atrial Fibrillation: Peak digoxin body stores larger than the 8 to 12 mcg/kg required for most patients with heart failure and normal sinus rhythm have been used for control of ventricular rate in patients with atrial fibrillation.

Doses of digoxin used for the treatment of chronic atrial fibrillation should be titrated to the minimum dose that achieves the desired ventricular rate control without causing undesirable side effects. Usual Pediatric Dose for Atrial Fibrillation: Do not give full total digitalizing dose at once. Administer loading doses in several portions, give roughly half the total as the first dose. Give additional fractions of the total dose at 6 to 8 hour intervals (oral) or 4 to 8 hour intervals (parenteral). Divided daily dosing is recommended for infants and young children under 10 years of age. Parenteral administration should be used only when the need for rapid digitalization is urgent or when the drug cannot be taken orally. Intravenous administration is preferred over intramuscular injection as it can lead to severe pain at the injection site. If it is necessary to administer the drug by the intramuscular route, it should be injected deep into the muscle followed by massage. No more than 500 mcg should be injected into a single site. Calculated doses should be based on lean body weight.

Premature: Digitalizing (Loading) dose: Oral elixir: 20 to 30 mcg/kg; Intravenous: 15 to 25 mcg/kg Maintenance dose: oral 5 to 7.5 mcg/kg; intravenous 4 to 6 mcg/kg Full Term: Digitalizing (Loading) dose: Oral elixir: 25 to 35 mcg/kg; Intravenous: 20 to 30 mcg/kg Maintenance dose: oral 6 to 10 mcg/kg; intravenous 5 to 8 mcg/kg 1-24 months: Digitalizing (Loading) dose: Oral elixir: 35 to 60 mcg/kg; Intravenous: 30 to 50 mcg/kg Maintenance dose: 10 to 15 mcg/kg oral; intravenous 7.5 to 12 mcg/kg 3 to 5 years: Digitalizing (Loading) dose: Oral elixir: 30 to 40 mcg/kg; Intravenous: 25 to 35 mcg/kg Maintenance dose: oral 7.5 to 10 mcg/kg

; intravenous 6 to 9 mcg/kg 6 to 10 years: Digitalizing (Loading) dose: Oral elixir: 20 to 35 mcg/kg; Intravenous: 15 to 30 mcg/kg Maintenance dose: oral 5 to 10 mcg/kg; intravenous 4 to 8 mcg/kg 11 years and older: Digitalizing (Loading) dose: Oral elixir: 10 to 15 mcg/kg; Intravenous: 8 to 12 mcg/kg Maintenance dose: oral 2.5 to 5 mcg/kg; intravenous 2 to 3 mcg/kg What other drugs will affect digoxin?

Other drugs may interact with digoxin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using. Where can I get more information? Your pharmacist can provide more information about digoxin. Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use digoxin only for the indication prescribed. Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners.

The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist. Copyright 1996-2017 Cerner Multum, Inc. Version: 8.04. Revision Date: 2015-08-31, 8:25:50 AM. Drug Status Digitalis - used, anesthetic, blood, body, produced, plant, Foxglove, The Pharmacy in the Garden, Witherings Studies Medical Discoveries » Com-En » Digitalis Digitalis Doctors often treat illnesses with drugs derived (obtained) from special substances found in plants. One of the most important of these drugs is digitalis, which is used to treat congestive heart failure.

This heart condition occurs when the heart becomes enlarged and loses some of its effectiveness in pumping blood. Swelling caused by an accumulation of fluid in the arms and legs or hands and feet may be a sign of congestive heart failure. As long ago as the thirteenth century, people who used "folk" remedies began to notice that a plant commonly known as foxglove produced a medicine that could be used to treat some types of this swelling, called "dropsy." The medical term for swelling caused by a buildup of fluid is edema. Digitalis is one of the most useful drugs in treating heart disease. It works by making the heart's contractions stronger without causing it to beat faster and become overworked. This results in a slower, more effective heartbeat with longer periods of rest for the heart in between. Digitalis. Digitalis is one of the most famous medicines derived from a plant. Foxglove Common foxglove is grown in gardens as a popular flower and also grows wild along roadsides and in meadows or logged areas, mainly in the western United States. The botanical name for common foxglove is Digitalis purpurea. Foxglove was brought to the United States by European migrants centuries ago.

The plant has tube-shaped, spotted, purple flowers and grows to about five feet tall, with many large, thick, hairy leaves at the base of a tall stem. The variety grown in gardens varies in color from white to a deep rose. Digitalis is one of the most well known medicines derived from a plant. Today scientists are searching in jungles and tropical rain forests for other plants that may contain substances to cure cancer, hepatitis, AIDS, and other serious diseases. Native medicine healers have used plants to treat illnesses among their people for thousands of years, and scientists today are working with modern-day medicine men in hopes of finding new wonder drugs among the earth's fast-disappearing natural resources.

The Pharmacy in the Garden Other drugs used today that come from plants include tubocurarine, a surgical anesthetic derived from the curare vine; ephedrine, the active ingredient in decongestants, found in the stem of a Chinese shrub called mahuang; the opium poppy, which contains more than 20 alkaloids, of which morphine, codeine, and heroin are the most well known; aspirin, a painkiller derived from willow tree bark; reserpine, an anti-hypertensive that comes from the snakeroot plant; atropine, an intestinal (smooth muscle) antispasmodic and pupil dilator found in belladonna (deadly nightshade); and physostigmine, a glaucoma treatment and atropine poisoning antidote (remedy) derived from the Calabar bean. Withering's Studies In 1775 an English doctor named William Withering (1741-1799) began studying the foxglove plant. He learned that an effective medicine for treating heart ailments could be made from drying leaves picked just before the plant blossomed and crushing them into a powder.

Withering also discovered that this medicine, digitalis—one of a number of substances called found in the plant—could be poisonous if the patient was given too much. Withering was aware that digitalis was effective only in certain forms of dropsy (edema), but apparently did not associate this with the cardiac actions of the drug. Withering published his findings about digitalis in 1785, but in spite of his warnings about proper dosage, many doctors prescribed the medicine in doses that were too large and for sicknesses it could not cure. The active principles of digitalis were not known to researchers until the mid-1800s, when two French scientists, Homolle Ouevenne and Theodore Ouevenne, found the substance digitalin in the foxglove plant. In 1875 Oscar Schmiedeberg (1838-1921) identified the potent chemical digitoxin in the plant, and in 1930 the English chemist Sydney Smith obtained the medicine used today, digoxin, from the wooly foxglove plant, Digitalis lanata.

Today doctors know that if too much digitalis enters the circulatory system the patient may experience nausea, vomiting, trouble with vision (seeing too much yellow or green), and a very slow and irregular heartbeat. A larger amount of digitalis can result in convulsions (severe seizures) and death. Even grazing animals that eat too much of the foxglove plant can become poisoned by its glycosides. User Contributions: Origins of Medicine: Foxglove Plants Origins of Medicine: Foxglove Plants Herbal ­medicine’s Femme Nikita By Steven Foster Think of Foxglove as the Femme Nikita of herbs— beautiful, potentially deadly, and invaluable when used properly. Foxglove contains substances that are among the most potent heart treatment drugs used today, but they can be lethal if used incorrectly. William Withering’s Digitalis Discovery "In the year 1775, my opinion was asked concerning a family receipt for the cure of the dropsy. I was told that it had long been kept a secret by an old woman in Shropshire, who had sometimes made cures after the more regular practitioners had failed.

I was informed also, that the effects produced were violent vomiting and purging; for the diuretic effects seemed to have been overlooked. This medicine was composed of twenty or more different herbs; but it was not very difficult for one conversant in these subjects, to perceive, that the active herb could be not other than the Foxglove.” —from William Withering’s An Account of the Foxglove and Some of Its Medical Uses: With Practical Remarks on Dropsy, and Other Diseases published in 1785. Despite the danger, physicians and herbalists have long turned to foxglove to treat a variety of disorders, including tuberculosis and edema. But it wasn’t until the twentieth century that health practitioners made the link between foxglove and congestive heart failure (CHF), and that medicines derived from the plant were developed into prescription drugs. Foxglove contains the cardiac glycosides digitoxin (from Digitalis ­purpurea and D. lantana) and digoxin (from D. lantana).

All of foxglove’s glycosides, known collectively as digitalis, increase the force of heart ­contractions, leading to more efficient movement of blood through the heart and giving the heart more resting time between contractions. ­Glycosides also correct abnormal rhythms such as atrial fibrillation and atrial flutter, and act as a diuretic, an effect that arises more from improved ­circulation than from a direct impact on the kidneys. While such qualities make digitalis a valuable treatment for CHF, it has drawbacks. One is a narrow therapeutic window that allows desired outcomes only within a small dosage range. Amounts higher than the range can be deadly or, at minimum, cause gastrointestinal discomforts such as depressed appetite, nausea, and vomiting; neurological side effects, such as dizziness, fatigue, and hallucinations; and cardiac system problems, including abnormal heart rhythms. To underscore the deadly power digitalis can wield, between 1993 and 1995, four previously healthy men, including a twenty-three-year-old and a twenty-six-year-old, died after taking an aphrodisiac that left abnormally high amounts of digoxin in their blood.

In addition, foxglove is by itself a poison­ous plant. Do NOT eat it out of your garden, nor try to make your own medicines from it. And use ­digitalis-derived medicines only as recommended by your physician, who will carefully monitor you for ill effects. Practitioners who emphasize natural healing usually prefer to bolster a failing heart with other, milder herbs, notably hawthorn (Crataegus spp). Foxglove’s Long and Tangled Past Despite the drawbacks, the fact is that foxglove has contributed enormously to modern medicine. The name foxglove probably comes from the Anglo-Saxon word foxes-glew, meaning fox music. Apparently, the bell-like flowers resembled an ancient musical instrument whose bells hung from an arched support. In Scandinavian dialects, the name means foxes-bell. Herbalists first began experimenting with foxglove centuries ago. They created a powder of the leaves and prescribed it for internal cleansing. They noted a constellation of side effects, ranging from vomiting to death, and described foxglove as a violent medicine.

Medieval healers used the plant externally, and records from the early Renaissance focus on foxglove’s external use as an ointment for treating wounds, ulcers, and other conditions. Foxglove was first mentioned to treat “feebleness of the heart” in 1526 by Peter Treveris in his Grete Herball. The sixteenth-century German botanist Leonhardt Fuchs wrote about foxglove in an important herbal published in 1542. To him, the flowers ­resembled the single digit of a glove (fingerhut in German), so he gave the plant its genus name, Digitalis—which contains the root word digit, or ­finger. In Theatrum Botanicum published in London in 1640, John Parkinson recommended the herb for tuberculosis of the lymph nodes in the neck. People also called this malady “the King’s Evill” because they believed that a royal touch could cure it. “The herb bruised or the juice made up into an ointment and applied to the place, hath been found by late experience to be available for the King’s Evill,” wrote Parkinson, an herbalist and apothecary.

Until the late eighteenth century, information on foxglove consisted of anecdotes about its use as a folk medicine. But in 1785, the British physician William Withering introduced the herb to the medical establishment with the publication of An Account of the Foxglove and Some of Its Medical Uses: With Practical Remarks on Dropsy, and Other Diseases. Withering came to know foxglove as an important medicinal after he heard a rumor of foxglove’s use by “an old woman in Shropshire.” He recognized that digitalis affected the heart, but he mistakenly believed that it acted primarily on the kidneys as a ­diuretic. After Withering’s discovery, foxglove leaf became a standardly prescribed drug in medical practice, primarily as a diuretic to treat “dropsy,” an excess accumulation of fluid in connective tissue, known today as edema. It was also mistakenly prescribed for maladies ranging from asthma to insan­ity. But physicians soon began to observe its effects on the heart.

In his 1789 edition of the Edinburgh New Dispensatory, Andrew Duncan wrote, “During its operation it has often very remarkable influence in rendering the pulse slower; and it frequently excites very considerable vertigo, and an affection of vision.” Knowing the Foxglove The genus Digitalis contains ­nine-teen species from the figwort family Scrophulariaceae, most of them native to central and Western Europe and Central Asia. At least thirteen species grow in American gardens, but D. purpurea, or purple foxglove, is most common. Foxglove also grows wild in some parts of North America, blossoming along roadsides from Vancouver Island to Northern California and occasionally in the northeast countryside. A biennial, D. purpurea grows up to six feet tall. It produces no flowers during its first year, but it does produce a rosette of blunt-toothed leaves. People have eaten these leaves, mistaking them for comfrey, with dire—even fatal—consequences. In its second year of growth, foxglove shoots up a spike of beautiful purple, pink, or white thimble-shaped flowers; some species (D. lutea and D.

grandiflora) have yellow flowers. A More Precise Picture By the mid-nineteenth century, physicians viewed foxglove as a narcotic, diuretic, and sedative with remarkable effects on the heart, including reducing the frequency of the pulse. A clearer understanding of digitalis came as the pharmacy sciences shifted from focusing on the identification and standardization of drugs to studying their effect on living ­organisms. In 1883, Oswald Schmiedeberg, a renowned German pharmacologist, published findings that attributed foxglove’s effects to its glycosides. And in 1905, the British Medicinal Journal published results of experiments conducted by Sir James Mackenzie, a Scottish physician who used a pulse-measuring device to record the effects of digitalis. From the late 1800s to about 1930, researchers more precisely isolated cardiac glycosides such as digitoxin and digoxin, and these compounds came to be manufactured and prescribed as drugs. Although physicians knew that the compounds could be toxic, they valued them for their potent effect on the heart—and they still do.

Thanks to Withering, an observant and open-minded physician, foxglove has evolved from a folk remedy to a powerful medicine—one that has saved countless lives. Steven Foster, an Herbs for Health editorial adviser, is author of Herbs for Your Health (Interweave Press, 1996), and 101 Medicinal Herbs—An Illustrated Guide, due this fall from Interweave. Digoxin Digoxin Skip to the navigation Drug Information Digoxin is a drug originally derived from the foxglove plant, Digitalis lanata. Digoxin is used primarily to improve the pumping ability of the heart in congestive heart failure (CHF). It is also used to help normalize some dysrhythmias (abnormal types of heartbeat). Common brand names: Digitek, Lanoxicaps, Lanoxin, Lanoxin Pediatric Summary of Interactions with Vitamins, Herbs, & Foods Types of interactions: Beneficial Adverse Check Replenish Depleted Nutrients Magnesium People needing digoxin may have low levels of potassium or magnesium,1 increasing the risk for digoxin toxicity.

Digoxin therapy may increase magnesium elimination from the body.2 People taking digoxin may benefit from magnesium supplementation.3 Medical doctors do not commonly check magnesium status, and when they do, they typically use an insensitive indicator of magnesium status (serum or plasma levels). The red blood cell magnesium level may be a more sensitive indicator of magnesium status, although evidence is conflicting. It has been suggested that 300–500 mg of magnesium per day is a reasonable amount to supplement.4 Reduces Effectiveness St. John’s Wort One preliminary trial has suggested that St. John’s wort(Hypericum perforatum) may reduce blood levels of digoxin.5 In this study, healthy volunteers took digoxin for five days, after which they added 900 mg per day of St. John’s wort while continuing the daily digoxin. A normal blood level of digoxin was reached after five days of taking the drug, but this level dropped significantly when St. John’s wort was added. This may have occurred because certain chemicals found in St.

John’s wort activate liver enzymes that are involved in the elimination of some drugs.6 , 7 Until more is known, people taking digoxin should avoid St. John’s wort. The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence. Potential Negative Interaction Loss of potassium due to cascara (Rhamnus purshiani cortex) abuse could theoretically increase the effects of digoxin and other similar heart medications, with potentially fatal consequences. However, no cases of such an interaction have yet been reported. The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence. Digitalis Digitalis (Digitalis purpurea) refers to a group of plants commonly called foxglove that contain chemicals with actions and toxicities similar to digoxin. Digitalis was used as an herbal medicine to treat some heart conditions before the drug digoxin was available. Some doctors continue to use digitalis in the United States, and it is used as an herbal medicine in other countries as well. Due to the additive risk of toxicity, digitalis and digoxin should never be used together. The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

Eleuthero People taking digoxin require regular monitoring of serum digoxin levels. In one report, addition of a product identified as Siberian ginseng to stable, therapeutic digoxin treatment was associated with dangerously high serum digoxin levels.10 The patient never experienced symptoms of digoxin toxicity. Laboratory analysis found the product was free of digoxin-like compounds but the contents were not further identified. This report may reflect an interaction of eleuthero with the laboratory test to cause a falsely elevated reading, rather than actually increasing digoxin levels. The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence. Licorice Potassium deficiency increases the risk of digoxin toxicity. Excessive use of licorice plant or licorice plant products may cause the body to lose potassium.11 Artificial licorice flavoring does not cause potassium loss. People taking digoxin should read product labels carefully for licorice plant ingredients. The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

Explanation Required Hawthorn Hawthorn (Crataegus oxyacantha, Crataegus monogyna) (leaf with flower) extract is approved in Germany to treat mild congestive heart failure .12 Congestive heart failure is a serious medical condition that requires expert medical management rather than self-treatment. Due to the narrow safety index of digoxin, it makes sense for people taking digoxin for congestive heart failure to consult with their doctor before using hawthorn-containing products. Reports of hawthorn interacting with digitalis to enhance its effects have not been confirmed. Alder Buckthorn Use of buckthorn (Rhamnus catartica, Rhamnus frangula, Frangula alnus) or alder buckthorn for more than ten days consecutively may cause a loss of electrolytes (especially the mineral potassium). Loss of potassium may increase the toxicity of digitalis-like medications with potentially fatal consequences.13 The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

Buckthorn Use of buckthorn (Rhamnus catartica, Rhamnus frangula, Frangula alnus) or alder buckthorn for more than ten days consecutively may cause a loss of electrolytes (especially the mineral potassium). Loss of potassium may increase the toxicity of digitalis-like medications with potentially fatal consequences.14 The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence. Potassium Medical doctors prescribing digoxin also check for potassium depletion and prescribe potassium supplements if needed. Potassium transport from the blood into cells is impaired by digoxin.15 Although digoxin therapy does not usually lead to excess potassium in the blood (hyperkalemia), an overdose of digoxin could cause a potentially fatal hyperkalemia.16 People taking digoxin should therefore avoid taking potassium supplements, or eating large quantities of fruit (e.g., bananas), unless directed to do so by their doctor. On the other hand, many people taking digoxin are also taking a diuretic; in these individuals, increased intake of potassium may be needed. These issues should be discussed with a doctor.

The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence. Senna Bisacodyl , a laxative similar in action to senna (Cassia senna, Cassia angustifolia), givenwith digoxin decreased serum digoxin levels in healthy volunteers compared with digoxin alone.17 In patients taking digoxin, laxative use was also associated with decreased digoxin levels.18 In addition, concern has been expressed that overuse or misuse of senna may deplete potassium levels and increase both digoxin activity and risk of toxicity.19 However, overuse of senna could also decrease digoxin activity because, as noted, laxatives can decrease the levels of the drug. The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence. The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers’ package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a new supplement with your doctor or pharmacist. References 1.

Whang R, Oei TO, Watanabe A. Frequency of hypomagnesiumia in hospitalized patients receiving digitalis. Arch Intern Med 1985;145:655-6. 2. Holt GA. Food & Drug Interactions. Chicago: Precept Press, 1998, 94. 3. Landauer RA. Magnesium deficiency and digitalis toxicity. JAMA 1984;251:730 [letter/review]. 4. Cohen L, Kitzes R. Letter. JAMA 1984;251:730. 5. Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45. 6. Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St.

John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502. 7. Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45. 8. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide for Health-Care Professionals. London: Pharmaceutical Press, 1996, 213-4. 9. Bradley PR (ed). British Herbal Compendium, vol 1. Bournemouth, Dorset, UK: British Herbal Medicine Association, 1992, 194-6. 10. McRae S. Elevated serum digoxin levels in a patient taking digoxin and Siberian ginseng. Can Med Assoc J 1996;155:293-5.

11. Tyler VE. The Honest Herbal, 3rd ed. New York: Pharmaceutical Products Press, 1993, 198. 12. Blumenthal M, ed. The Complete German Commission E Monographs. Austin, TX: American Botanical Council, 1998, 143. 13. European Scientific Cooperative on Phytotherapy (ESCOP). Frangulae cortex, frangula bark. Monographs on the Medicinal Uses of Plant Drugs. Exeter, UK: University of Exeter, Centre for Complementary Health Studies, 1997. 14. European Scientific Cooperative on Phytotherapy (ESCOP). Frangulae cortex, frangula bark. Monographs on the Medicinal Uses of Plant Drugs. Exeter, UK: University of Exeter, Centre for Complementary Health Studies, 1997. 15. Lown B, Black H, Moore FD. Digitalis, electrolytes and the surgical patient. Am J Cardiol 1960;6:309-37. 16. Smith TW, Willerson JT. Suicidal and accidental digoxin ingestion.

Report of five cases with serum digoxin level correlations. Circulation 1971;44:29-36. 17. Wang DJ, Chu KM, Chen JD, et al. Drug interaction between digoxin and bisacodyl. J Formos Med Assoc 1990;89:913, 915-9 [in Chinese]. 18. Botzler R, Ritter U. Effect of laxative measures on the serum concentration of digoxin in the human. Leber Magen Darm Nov 1982; 14(6):255-7 [in German]. 19. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide for Healthcare Professionals. London: Pharmaceutical Press, 1996, 244.

Digoxin from foxgloves 'helps blood pressure, heart failure' - Health News - NHS Choices Monday June 18 2012 Digoxin (made from foxgloves) is used to treat heart disease An “extract from poisonous Foxglove can protect against high blood pressure and heart failure”, the Daily Mail has reported. It does this by enhancing the mechanism the body uses to protect itself against the conditions, the Mail says. This story is based on laboratory research into the potential role of the drug digoxin (which is extracted from the foxglove plant) in treating heart conditions such as high blood pressure and heart failure. Digoxin is currently used to control heart rate in some patients with an irregular heartbeat, and has been shown to improve heart failure symptoms. However, the fact that it can be poisonous and needs to be monitored means that it is not commonly prescribed. The current study identified a protein that is involved in the prevention of high blood pressure. The researchers scanned a library of thousands of existing drug compounds to identify ones that could potentially treat the condition. They found that digoxin was able to increase the presence of this protein in both cells in the lab and living mice.

The researchers conclude that this may explain how digoxin improves heart failure symptoms, and suggest it may offer a new approach for treating heart conditions. This was an early stage drug discovery study. It will probably take several years of continued research into the effectiveness and safety of digoxin for high blood pressure patients before the drug could be available for treating the condition. Where did the story come from? The study was carried out by researchers from the University of Michigan and the University of Toledo in the United States, and was funded by the US National Institutes of Health and the Swedish Heart and Lung Foundation. The study was published in the peer-reviewed journal Molecular Pharmacology. The Mail’s headline emphasising the poisonous nature of the foxglove extract is misleading, as is its discussion of the use of foxglove extract in the 13th century and Victorian times. While digoxin may have been used throughout history for various purposes and can be poisonous, it is a licensed treatment for certain heart conditions. However, it takes the body a long time to break down digoxin and, as such, treated patients, particularly the elderly, can be at risk of adverse effects due to toxic levels of digoxin building up in the body.

Toxic levels of digoxin can cause heart problems, giving rise to symptoms similar to those it is used to treat. For this reason, digoxin can be a difficult drug to use, and levels in the blood sometimes have to be monitored to ensure that it is not building up to toxic levels. What kind of research was this? This research was carried out in cell cultures and animals. It aimed to identify an existing medicine that could target a specific protein, RGS2. This protein is important for normal heart function, and low levels of RGS2 are associated with high blood pressure (hypertension) and heart failure. The researchers thought that a drug that targets RGS2, increasing its production, could provide a new approach to treating these common conditions. Cell and animal studies are a vital part of the drug discovery and drug development process. They can provide an early indication of the potential action of new drugs or, in this case, the potential action of old drugs in treating a new condition. They can also be useful in studying the specific mechanisms by which drugs work. However, they cannot tell us whether a drug will effectively and safely treat a condition in real patients. Further clinical trials in humans are required to assess these factors.

What did the research involve? The researchers identified a protein, RGS2, which is found in low levels in some patients with high blood pressure and heart failure. They tested thousands of drugs to see whether or not they could increase the levels of RGS2 in cells. The selected drug compounds were then tested in mice. The animals were given the drugs for seven days, and then their heart tissue was tested for RGS2 levels. The researchers analysed the data to determine whether or not there was a dose-response relationship between drug treatment and RGS2 protein levels. What were the basic results? The researchers found that digoxin, and other similar drugs (digoxin was the only currently licensed medical drug used in the study), led to a two to three fold increase in RGS2 protein levels in cells. The change in RGS2 levels was both concentration and time dependent, with higher levels seen at greater digoxin levels, and the levels decreasing over time after exposure to the compound. Mice treated with digoxin for seven days showed increased levels of RGS2 in both heart and kidney tissues compared with mice that were not treated with the drug. How did the researchers interpret the results?

The researchers conclude that digoxin, a drug currently used to treat heart failure and certain heart rhythm problems, could be used for the treatment of high blood pressure. Conclusion This early stage drug discovery study suggests that digoxin may have potential use in the treatment of high blood pressure. However, much more research is needed to determine whether the drug is safe and effective for treatment of patients with hypertension. Digoxin is a chemical found in the foxglove plant. It is a drug that increases the force of heart contraction, and also slows the conduction of electrical impulses through the heart. As such, digoxin is currently licensed to treat heart failure and certain heart rhythm problems. However, the risk of the drug building up to toxic levels in the body, which is particularly dangerous in the elderly, means that its use within the medical profession is often quite limited. The exact mechanism by which digoxin improves heart function is not known. This research suggests that its role in increasing RGS2 levels may account for some of its clinical impact in the treatment of heart failure. Further research is required to determine whether this is the case, however.

The researchers say that, at this stage in the research, it is not possible to say whether the increased levels of RGS2 seen after treatment with digoxin will translate into a functional effect. They say that the effects of continuous digoxin treatment, and associated increases in RGS2 levels, are not known, and will need to be investigated in future studies. Overall, this study provides additional knowledge that may be helpful in developing new drugs for heart conditions, and understanding how current cardiac therapies work. It has, however, little immediate relevance for patients with high blood pressure. Analysis by Bazian . Edited by NHS Choices . Analysis by Edited by NHS Choices Links to the headlines How extract from poisonous Foxglove can PROTECT against high blood pressure and heart failure . Daily Mail, Published June 15 2012 Links to the science Sjogren B, Parra S, Heath LJ, et al. Cardiotonic Steroids Stabilize RGS2 Protein Levels . Molecular Pharmacology.

Published online June 13 2012, doi:10.1124/mol.112.079293 Further reading Digitalis purpurea (common foxglove) | Plants & Fungi At Kew Discover plants and fungi Digitalis purpurea (common foxglove) A popular ornamental, with tall spires of tapered, tubular, purple to pink or white flowers, common foxglove is also a source of digitoxin, used in the heart drug digitalis. Digitalis purpurea (common foxglove) common foxglove, purple foxglove, fairy fingers, fairy gloves, fairy bells, floppy dock, tod-tails Conservation status: Not threatened. Not evaluated according to IUCN Red List criteria. Habitat: Open places, especially woodland clearings, heaths and mountainsides and also waste ground (especially on disturbed sites and as a pioneer on burnt areas); on acid or calcareous soils; also as a garden escape. Key Uses: Ornamental, medicinal. Known hazards: All parts of the plant are poisonous if eaten. Contact with plant material can cause irritation.

Taxonomy Genus: Digitalis About this species Digitalis purpurea was named by the Swedish botanist Carl Linnaeus in his pivotal publication Species Plantarum in 1753. The generic name Digitalis comes from the Latin for finger (digitus), referring to the shape of the flowers. The specific epithet purpurea refers to the colour of the flowers, which are frequently purple (although a white-flowered form is fairly common). Common foxglove is a popular ornamental, and many hybrids and cultivars are available. Genus: Discover more Geography and distribution Common foxglove is thought to be native to west, south-west and west central Europe, and to be widely naturalised further east. Its exact status, whether truly native or naturalised, in each country is unknown, but it is possibly native in the following countries: Belgium, the Czech Republic, France, Germany, the United Kingdom, Ireland, Italy (Sardinia), Luxembourg, Norway, Portugal, Slovakia, Spain and Sweden (and perhaps also Austria, Denmark, Hungary, The Netherlands and Poland). It is naturalised in North America, and is listed as an ‘invasive and noxious weed’ by the United States Department of Agriculture.

Description Fruit of Digitalis purpurea Overview: An erect biennial (or short-lived perennial), growing up to 2 m tall, with a downy covering of hair. Leaves: The basal leaves are ovate to lanceolate and are borne on a winged petiole (leaf stalk) of 3–12 cm long. Flowers: The flowers are borne on a simple or sparsely branched raceme with un-stalked bracts; the upper bracts are sometimes minute. The pedicels (individual flower stalks) are 11–20 mm long and hairy. The corolla (petals) is purple to pale pink or white, 40–55 mm long, and is usually marked on the inside with dark purple spots edged with white. Fruits: The fruit is an ovoid capsule of 11 x 7 mm, equal to or longer than the calyx (sepals). The brown, rectangular seeds are almost 1 mm long, with a network of ridges across the surface. The flowers usually open between June and September and are pollinated by bumblebees.

Uses Common foxglove (Photo: Wolfgang Stuppy) Common foxglove is cultivated for its ornamental value, and many hybrids (with other Digitalis species) and cultivars are available. It is also grown to attract bumblebees to gardens. Its flowers provide food for larvae of the foxglove pug moth (Eupithecia pulchellata) and it is also a food plant for larvae of the frosted orange moth (Gortyna flavago). Digitalis purpurea also contains loliolide, a potent ant-repellent which was once used as an insecticidal disinfectant for walls in the Forest of Dean, England. Medicinal uses Foxgloves are a source of digitoxin, a glycoside used in the drug digitalis, which has been used as a heart stimulant since 1785. It is also well-known for its toxicity, and ingestion of the leaves (usually as a result of misidentification for comfrey, Symphytum officinale) can result in severe poisoning. Despite their toxicity, they have been widely used in folk-medicine.

Foxglove tea (an infusion of the leaves) was taken for colds, fevers and catarrh, and compresses were used for ulcers, swellings and bruises. Its most common use was as a diuretic against dropsy (accumulation of fluid in the tissues), for which it was sometimes effective, but occasionally proved fatal. William Withering, an 18th century botanist and physician, studied the medicinal use of foxgloves, in particular their use in the treatment of dropsy. He discovered that an infusion of the leaves could slow and strengthen the heartbeat, which in turn stimulated the kidneys to clear the body and lungs of excess fluid. He also showed that foxglove leaves could be used in the treatment of heart failure (but that high doses could stop the heart). Withering’s An Account of the Foxglove and Some of its Medical Uses: with Practical Remarks on Dropsy, and Other Diseases (1785) is a landmark publication, being the first English text in which the therapeutic effects of a drug are described, and is considered by some to mark the birth of modern pharmacology.

Withering’s work led to the eventual isolation and purification of digitoxin and digoxin (cardiac glycosides used in modern medicine as heart stimulants in the drug digitalis). Today, digitalis is normally made using Digitalis lanata leaves (although during the Second World War D. purpurea seeds were collected from the wild and grown to produce large quantities of leaves for medicinal use). Toxicity of foxgloves The main toxins in Digitalis species are cardiac glycosides, which are present in all parts of the plant. The flowers contain the lowest concentration of toxins, yet their ingestion can still result in gastrointestinal effects. The ingestion of leaves can cause oral and abdominal pain, nausea, vomiting and diarrhoea. In severe cases, symptoms can include visual and perceptual disturbances and heart and kidney problems. There have been many reported cases of poisoning, for example when foxglove leaves have been mistakenly collected by those wishing to make comfrey (Symphytum officinale) herbal tea. Seeds of Digitalis purpurea Millennium Seed Bank: Seed storage Kew's Millennium Seed Bank Partnership aims to save plant life world wide, focusing on plants under threat and those of most use in the future.

Seeds are dried, packaged and stored at a sub-zero temperature in our seed bank vault. A collection of Digitalis purpurea seeds is held in Kew’s Millennium Seed Bank based at Wakehurst in West Sussex. This species at Kew Close up of common foxglove (Photo: Wolfgang Stuppy) Digitalis purpurea can be seen growing wild in the grounds of Queen Charlotte's Cottage at Kew. It is also grown in the Queen’s Garden (behind Kew Palace), the Secluded Garden, and the Woodland Garden around the Temple of Aeolus. Extensive areas of foxgloves can be seen in the woodlands at Wakehurst. Dried and spirit-preserved specimens of common foxglove are held in Kew’s Herbarium, where they are available to researchers by appointment. The details of some of these can be seen online in the Herbarium Catalogue. Specimens of Digitalis purpurea leaves, seeds, roots, wood, prepared digitalis BP, a ‘concentrated infusion of foxglove’, and digoxin tablets are held in Kew’s Economic Botany Collection in the Sir Joseph Banks Building, where they are available to researchers by appointment.

References and credits Aronson, J. K. (1985). An Account of the Foxglove and its Medical Uses, 1785-1985. Oxford University Press, Oxford. Dauncey, E. A. (2010). Poisonous Plants: A Guide for Parents & Childcare Providers. Royal Botanic Gardens, Kew. Huxley, A. (ed.) (1997). The New Royal Horticultural Society Dictionary of Gardening, Volume 2 (D-K). Macmillan Reference Ltd, London. Lin, C.-C., Yang, C.-C., Phua, D.-H., Deng, J.-F. & Lu, L.-H. (2010). An outbreak of foxglove leaf poisoning. Journal of the Chinese Medical Association 73: 97-100. Mabberley, D. J. (2008). Mabberley’s Plant-book: A Portable Dictionary of Plants, their Classification and Uses, 3rd Edition. Cambridge University Press, Cambridge. Mabey, R. (1997). Flora Britannica.

Chatto & Windus, London. Preston, C. D., Pearman, D. A. & Dines, T. A. (eds) (2002). New Atlas of the British and Irish Flora: An Atlas of the Vascular Plants of Britain, Ireland, the Isle of Man and the Channel Islands. Oxford University Press, Oxford. Royal Botanic Gardens Kew. (2008) Seed Information Database (SID). Version 7.1. Available online (accessed 22 February 2011). Stace, C. (1997). New Flora of the British Isles, 2nd Edition. Cambridge University Press, Cambridge. The Plant List (2010). Digitalis purpurea. Available online (accessed 06 February 2011). Kew science editor: Emma Tredwell Kew contributors: Steve Davis (Sustainable Uses Group) Copyediting: Emma Tredwell While every effort has been taken to ensure that the information contained in these pages is reliable and complete, the notes on hazards, edibility and such-like included here are recorded information and do not constitute recommendations.

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Question: From which plant do we derive the drug Digitalis?
Answer: Foxglove